In this paper I defend the compossibility of presentism and time travel from two objections. One objection is that the presentist’s model of time leaves nowhere to travel to; the second objection attempts to equate presentist time travel with suicide. After targeting some misplaced scrutiny of the first objection, I show that presentists have the resources to account for the facts that make for time travel on the traditional Lewisian view. In light of this ability, I argue that both of (...) the objections fail. (shrink)

To what extent is the scientist's endeavor qua scientist influenced by his philosophic image of himself? A preliminary and partial answer to this question is suggested by a study of eight physiological thinkers of the second half of the eighteenth century, a period during which biology was much influenced by the scientific and philosophical ideas of Isaac Newton. At this time, physiologists invoked certain "principles," "properties," and "powers" which were deemed useful as explanatory devices, even though they could not themselves (...) be explained. The use of these devices in physiology was often defended in terms of their supposed similarity to devices used in mathematics and Newtonian physics. The results of this practice are considered critically, partly in the light of current studies of scientific explanation. (shrink)

This essay explicates a structural theory of the historical evolution of world-systems. Rather than using societies as the unit of analysis the authors use intersocietal interaction networks (world-systems). This enables them to take theoretical account of the systemic development processes that are regional and inter-regional in scope and to formulate a more powerful theory that explains how thousands of egalitarian small-scale world-systems evolved, expanded and merged to become the hierarchical and global world-system of today.